From the article:
Exercise-induced anapylaxis is likely to involve both TRPV1 and TRPA1 ion channels. Exercise is an oxidative state, with the individual consuming more oxygen and generating a range of compounds including superoxide anions, hydoxyl radicals, and hydrogen perioxide. TRPA1 is the main oxidant receptor and the ion channel activates on sensing these irritant compounds. Importantly, it acts as a direct sensor of oxygen and is activated during hypoxia. Serotonin and bradykinin also increase with exercise influencing priming of TRPV1.